“More than 25% of patients with advanced NSCLC experience progression to the brain from their primary lung cancer and this number increases to 44-63% for those NSCLC tumors driven by EGFR mutations. Prognosis is poor and typically ranges for 1-5 months for those with brain metastases. EGFR TKIs are highly effective therapies for advanced NSCLC driven by EGFR mutations, especially the common mutations, exon 19 deletions and L858R point mutations. Even though there are a number of EGFR TKIs approved for first-line therapy of EGFR mutation positive NSCLC, there is a scarcity of prospective data for EGFR TKIs in patients with brain metastases.”